How Do Auto-Expiring Topics Work?
Topic threads on RStudio Community automatically close (See 
icon) after a certain amount of time.
Once they are closed, regular users are not able to reply to them.
If you have an issue related to this thread, please start a new topic-thread with appropritae category and tags, and refer back to the closed topic with a link.
What motivates this policy?
Why auto-close instead of keeping threads open forever? We used to have threads open indefinitely but found that too often follow-up reply-posts were only tangentially related to the original topic. Each reply then alerts every participant in that thread, leading to an overload of notifications. With the goal of keeping things succinct and tidy, we introduced auto-closing.
For now, with R and data science moving so fast, it seems reasonable to ask an almost identical question every new year, with the new thread dedicated to the latest technologies, resources, and best practices, without being bogged down by all the old, often deprecated discussion.
That motivated the added text "If you have a query related to it or one of the replies, start a new topic and refer back with a link." in the thread-closing message.
Why do some topic-threads close after varying amounts of time? Some categories "go stale" at different speeds. For example, simple r-coding questions can usually be closed quickly, while shiny problems often take a while get sorted. And then things like Data Science Jobs & Gigs have their own fixed expirations.
Why are some old closed posted edited and replied to? - In a few cases, older topic-thread seemed to have struck a chord and receive a lot of page views. To make sure the throngs of people reaching a popular page receive what we think is the best advice, we might reply or edit the original post. This is don't ad-hoc.
This is all motivated in some older meta discussions
- expiration of community questions/posts - Why are Topic-Threads Automatically Closed After a Certain Amount of Time? - #3 by EconomiCurtis
- Why did you close a post & how can it be reopened again?